In-situ fabrication of on-chip 1T'-MoTe_(2)/Ge Schottky junction photodetector for self-powered broadband infrared imaging and position sensing

High-sensitivity room-temperature multi-dimensional infrared(IR)detection is crucial for military and civilian purposes.Recently,the gapless electronic structures and unique optoelectrical properties have made the two-dimensional(2D)topological semimetals promising candidates for the realization of multifunctional optoelectronic devices.Here,we demonstrated the in-situ construction of high-performance 1T’-MoTe_(2)/Ge Schottky junction device by inserting an ultrathin AlOx passivation layer.The good detection performance with an ultra-broadband detection wavelength range of up to 10.6 micron,an ultrafast response time of~160 ns,and a large specific detectivity of over 109 Jones in mid-infrared(MIR)range surpasses that of most 2D materials-based IR sensors,approaching the performance of commercial IR photodiodes.The on-chip integrated device arrays with 64 functional detectors feature high-resolution imaging capability at room temperature.All these outstanding detection features have enabled the demonstration of position-sensitive detection applications.It demonstrates an exceptional position sensitivity of 14.9 mV/mm,an outstanding nonlinearity of 6.44%,and commendable trajectory tracking and optoelectronic demodulation capabilities.This study not only offers a promising route towards room-temperature MIR optoelectronic applications,but also demonstrates a great potential for application in optical sensing systems.

An improved method of angle measurement with a position sensitive detector

An improved method of angle measurement is proposed based on a parallel plate interferometer. A position detection system is incorporated into a parallel plate interferometer in order to realize large deflection angle measurement. A reflecting mirror is introduced for increasing the measurement resolution. In experiments, a deflection angle of a measured target was measured within ～3° with high accuracy. And as a phase modulating interferometer, it was used to measure a small angular displacement with a repeatability of 5.5 × 10^-8 rad.

New test and analysis of position-sensitive-silicon-detector

We have tested and analyzed the properties of two-dimensional Position-Sensitive-silicon-Detector （PSD） with new integrated preamplifiers. The test demonstrates that the best position resolution for 5.5 MeV α particles is 1.7 mm （FWHM）, and the best energy resolution is 2.1%, which are notably better than the previously reported results. A scaling formula is introduced to make the absolute position calibration.

RF measurements of a C-band cavity beam position monitor

RF cold test of a novel C-band cavity beam position monitor （PBM） to be used in the SDUVFEL Test Facility is described. The test results are presented and some characteristics discussed. The main parameters obtained are in reasonable agreement with the analytical estimations. Effective suppression of the common mode has been demonstrated. The position sensitivity over the test region of μ0.5 mm is about -21.58 dB/10 μm for the TM110 mode and is linear in the central region of the BPM cavity.

Self-Collimation for Two-Dimensional Micro-Angle Measurement in Space

How to measure the two-dimensional attitude angle of space target and achieve stable tracking and aiming has become an important problem. The self-collimation is often measured via one-dimensional motion of the object in space. This paper proposes a micro-angle measurement system based on self-collimation to obtain the two-dimensional angle information of moving objects in space, and a thrice reflecting optical path structure is built to improve the compactness of the system. First, by establishing a posture angle measurement and decomposition model, the two-dimensional deflection angle value of the reflecting mirror is derived from the rotation angle equation;Second, the self-collimating measurement process is simulated to show the relationship between the reflecting mirror rotation angle and the imaging spot distortion of detector;Third, a two-dimensional micro-angle experimental platform is established based on the Position Sensitive Detector(PSD). Finally, nonlinear error of PSD is improved by the cubic spline interpolation method. The case results show a 15% reduction in the angle error.

Experimental research on a THGEM-based thermal neutron detector

A new thermal neutron detector with a domestically produced THGEM （Thick Gas Electron Multiplier） was developed as an alternative to 3He to meet the needs of the next generation of neutron facilities. One type of Au-coated THGEM was designed specifically for neutron detection. A detector prototype has been developed and the preliminary experimental tests are presented, including the performance of the Au-coated THGEM working in At/CO2 gas mixtures and the neutron imaging test with 252 Cf source, which can provide the reference for experimental data for research in the future.